I just posted some of this to another thread, but it belong here, too (and I want a Wii):
8 years ago, I was making $24,000 a year and needed to move on, make more money and establish a career. So, I ended up going to law school. But before I went to law school, I did calculations upon calculations. I calculated my ROI (Return on Investment) for three years lost income and the debt incurred. I compared business school to law school. And I eventually decided on law school. Ultimately, I figured that if I was near the top of my class, it was easily a successful investment.
I next had to turn to the "being near the top of my class" and I studied my ass off. I took out student loans to enable studying full-time. And it worked, I got a great job. Affter graduation, I ended up making twice what my projections were for. However, I would not have been at the top of my class had I gone part-time (they don't rank part-time students) and my grades would not have been as good if I had had double responsibilities. I could have held off on going to school, but I don't know when I would have saved enough to live for 3 years off my savings. I could be starting law school now at that rate. The only way for me to successfully give it my best shot was to go full-time and to do that I needed to take out debt.
Now, I don't recommend this as an "everyone should go to law school" post. There are a ton of stories out there which say not to. But for me, it feels really good to say "my best investment was in myself."